Aerofoil



LYSQOU Jan. 13, 193i. J. Q. HAMMETT AEROFOIL Filed Aprii 3. -1930 2 Sheets-Sheet l ln/manto@ Jan.`l3, 1931. J. Q. HAMMETT AEROFOIL Filed April 5, 1930 2 Sheets-Sheet 2 Patented Jan. 13, 1931 www@ UNITED STATES Y PATENT OFFICE JAQMES Q. HAMMETT, OF JUNCTION, TEXAS., ASSIGNOR OFAFORTY .PER CENT T LEN- ARD F. COWSERT AND TWENTY PER GENT T0 WILLIAM M. KEEN, :BOTH OF JUNC- AEROFOIL Application mea Aprila, 1930.- seriai No. 441,1as.

' or ailerons thereon allowing their\effective It is an accepted and generally used prin-` I ciple in aerodynamics that a small and 'rela-' tively narrow wing having aconcaved under surface may be mounted upon the leading edge of a sustaimng or main aerofoil or wing of an aircraft and arranged so that it may be raised and Ythrust forwardly from the main aerofoil in such manner that an' striking the wing assembly thus provided will be deflected by the concaved lower surface of the small wing and caused to follow the general contour of the .upper camber of the main aerofoil-.instead of being deflected upwardly in the greater part at an' angle from the aerofoil by the nose'thereof. In this manner the air stream-flowlng over the aerofoil is brought nearer the controls operation even at very slow speeds of the aircraft and reducing the danger in the op-,

eration thereof. Further advantages of the use of this arrangement arevwell known to those skilled in the art. y

It is the main objet of my invention to provide a device built into or formed integrally with the aerofoil or wing itself and adapted to continuously operate to provide the results attained by the structure as recited above without the necessity of operating mechanism of any sort.-

Another object is to provide a device for accomplishing the above results which may be readily and conveniently built into the Wing or aerofoil structure without weakening the same in any way.

A further object is to provide a device of the kind described which will be simple and cheap in construction and durable and efficient in use.

rIhe foregoing and other objects together with means whereby the same may be carried vinto effect will best be understood from the following description of a preferred embodiment of the invention taken in connection with the accompanying drawing where- 1n:

Figure 1 is a plan view of the end portion of an aerofoil to which vthe invention is applied; y

Figure 2 is an enlarged section along the line 2-2 in Figurev 1.

Figure 3 is a view similar` to Figure 2 and enlarged relative to the same, this view showing only the forward portion of the wing.

of the forward portion of a box for mountingin' the wing` to provide an air passageway.

Referring now more particularly to the drawing the reference numeral 1 designates an aerofoil or wing formed in the usual manner of a framework comprising a plurality of spaced ribs -2 connected by longitudinally extending spars 3, the whole being enclosed by the wing covering 4 of any suitable material. The ribs 2 are conventional Figure 4 1s an enlarged perspective .fview in form except that their nose portions 5 ity of the wing in the shoulders 6 disposed above the upper surface of the remainder of the wing. The usual' ailerons are 'provided on the wing 1 as designated at 7.

Between each rib 2 is disposed a box 8 of suitable material, the same comprising the sides 9, top and bottom 10 and 11 and the open ends as shown at 12 and 13. Each box 8 is secured by means of rivets 14 or any other suitable fastening means between the nose portions 5 of the said `ribs 2 with one open end 12 adjacent the leading edge of the wing and the other end 13 in alignment with the shoulders G formed onthe ribs, each box thus extendingangularly upward from their forward to their rear ends. The

Y top 10 of each box is arched or bowed uprupted passageways or shafts are -formed l 8 and be deflected downwardly bythe congare 2. Thus `it wi l be seen that a current o airv through the nose portion of the wing for.

the passage of the air.

It will now be understood that a portion of the air strikin the leading ed e of the wing in flight wi l pass through t e boxes caved undersides 15 of the tops 1 0 of the said boxes and will travel along the upper -surface of the win The path of this air stream is desi nate by the line A in Fi will be streaming past the ailerons 7 even at a very slow air speed allowing the effective operation of these control surfaces.

Another stream of airwill be deflected upwardly by the upper surface of the nose o the wing and will'take the course designated bythe line B in Figure 2. The s ace C between these lines A and B will inc ude a vacuumV equal to that created b any wing structure n'ow 1n use. However t 1s vacuum in the space willl be relieved of its drag on the wing by the movement therearound .-of relatively slow moving currents of lair corporatin which stray from the main air streams along the lines A and B thus making the ei'ective lift of a wing equipped wit invention considerably reater than an-ordinary wing. v This rel uction of drag on the w1n will also allow the use of a greater angle o attack, that is, .a greater angle between the chord of the wing and its motion of travel and will also allow the use of a full cambered wing with its lincreased lift. A further yadvantage .of the use of a wing inthe invention will be the reduced -hea resistance of the wing since the greater part'of the nose or leading ed e of the wing is open into the boxes 8.`

ddi-

are obtained by the use of t. e invention will be readily apparent to those skilled in theI art. l

Obviously -the passageways for the air may be built into or mounted on the'wing in various ways other than the `use of the vent boxes 8 as here shownand such variations in construction are considered within the scope of the invention.

While I have herein 'set forth a certain preferred embodiment of. the invention it is understood that Il may vary from the saine in minor structural details, so as best to construct a ractical device for the pur- I' poses intende not departing from' the spiritof the invention and within the scope ofv the appended claims.

the present`- tional advantages and-safet features which I claim:

1. In an aerofoil construction of the kind v described, an aerofoil, the nose portion there-y of being extended upwardly from the remainder of the aerofoil, a plurality of open ended boxes seated angularly in the aerofoil with their open ends communicatiner with the leading edge and rear edge of the upwardly extended nose portion thereof.

3. In an aerofoil construction` of the kind- |described, in combination with an aerofoil including a nose portion extended upwardly above the plane of the remainder of the aerofoil, the said aerofoil also including a plurality of spaced ribs, a plurality of boxesopen at their ends and comprising sides and top and bottom walls, the said boxes@l being secured by their sides to the said ribs 'with-y in the nose portion ofthe aerofoil vand with their open ends openin leading edge and rear o the said nose por.

tion of the aerofoil.

4. In an aerofoil construction ofthe kind described, in combination with an aerofoil' including a nose portion extended upwardly above the plane of the remainder of the aerofoil, the`said aerofoil also including a plurality of spaced ribs, a plurality of boxes open at their ends and comprising sides and top and bottom walls, the said boxes being secured by their sidesto the said ribs with- -i n the nose portion of the aerofoil and with their open ends opening out through the leadin edge and rear of the said nose portion o the aerofoil, the tops of the boxes being bowed upwardly to follow the contour of the u per surface of the nose portion of the aero oil.

5. In an aerofoil construction of the kind described,y an aerofoil having its nose portion extended upwardly beyond the plane of the remainder of the aerofoil, the said upwardly extended nose portion terminating at the center of gravity of the aerofoil, and an air passagewayv in the aerofoil extended angularly upward from the nose and terminatin at the rear edge of the said'upwardly exten ed nose portion. l

In testimony whereof I aix my signature.

JAMES Q, HAMMETT.

out through the 

